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- [6] Heterogeneity in R&D cooperation strategies[J] . René Belderbos,Martin Carree,Bert Diederen,Boris Lokshin,Reinhilde Veugelers.International Journal of Industrial Organization . 2004 (8)
- [7] Socioeconomic factors affecting the adoption potential of improved tree fallows in Africa[J] . S. Franzel.Agroforestry Systems . 1999 (1)